Application and study on preparation of bio-asphalt by modified phenolic resin from corn straw tar.

XPS, GPC, FT-IR, and GC-MS analyses were conducted on corn straw tar and 70# petroleum asphalt. The results indicate that the sulfur content in corn straw tar is lower than that in petroleum asphalt, potentially mitigating the volatilization of harmful substances upon substituting petroleum asphalt. This finding serves as evidence for the substantial presence of phenolic substances in corn straw tar. Upon employing the BOX-Behnken response surface analysis and utilizing resin yield as the evaluation index, the significance of three factors was established as follows: reaction time > phenol molar ratio > straw tar content. Based on the secondary multiple regression model, the optimal conditions for synthetic resin production are a phenolic mole ratio of 0.8, a reaction time of 125 min, and a straw tar dosage of 10 %. An assessment of resin viscosity at different VI temperatures reveals that corn stover tar can partially replace phenol and formaldehyde in the condensation reaction. Additionally, viscosity improvement is observed at elevated temperatures. Thermal gravimetric(TG) spectroscopy indicates lower mass loss in B-PF resin at high temperatures compared to PF resin or corn stover tar. In the evaluation of biological bitumen performance, it is discerned that the mixing amount of the prepared biological bitumen should be controlled at approximately 10 % of its performance. This ensures optimal efficacy without adversely affecting the performance of petroleum bitumen.

Risk factors for intraoperative hemorrhage during endoscopic submucosal dissection for colorectal lesions / 中华消化内镜杂志

Objective:To investigate the risk factors for intraoperative hemorrhage during endoscopic submucosal dissection (ESD) for colorectal lesions.Methods:Data of 386 patients with colorectal lesions, who underwent ESD at The Third People's Hospital of Datong and its cooperative hospital, Nanjing Drum Tower Hospital, from December 2019 to August 2021 were retrospectively analyzed. The patients were divided into the hemorrhage group ( n=85) and the non-hemorrhage group ( n=301) according to intraoperative hemorrhage. The correlationship of patients'basic information, lesion-related factors and hemorrhage during colorectal ESD was analyzed. Univariate and multivariate logistic regression were used to identify the risk factors for intraoperative hemorrhage during ESD. The risk predictive model of intraoperative hemorrhage during ESD was established according to the screened risk factors, and receiver operator characteristic (ROC) curve was used to evaluate the predictive model. Results:Univariate logistic regression showed that a history of diabetes ( OR=2.340, P<0.05), a history of coronary atherosclerotic heart diseases ( OR=3.100, P<0.05), the lesion located in the rectum ( OR=3.272, P<0.05), longer lesion ( OR=1.093, P<0.05), wider lesion ( OR=1.057, P<0.05), larger lesion ( OR=1.126, P<0.05), depressed lesion ( OR=6.128, P<0.05), the laterally spreading lesion ( OR=2.651, P<0.05), the lesion infiltrated into the SM-S layer ( OR=0.088, P<0.05), the lesion infiltrated into the SM-D layer ( OR=0.174, P<0.05), the diameter of hemorrhage vessels 0.5~<1.0 times of the diameter of incision knife ( OR=246.854, P<0.05), the postoperative pathology as early cancer ( OR=7.000, P<0.05) were risk factors for intraoperative hemorrhage during ESD. Considering the quantitative relationship between the length, the width and the area of lesions, multi-factor models were constructed using the length and area of lesions respectively. Forward stepwise regression was used to screen variables and determine the final model, and the results showed that a history of coronary atherosclerotic heart diseases, the depressed lesion, the longer lesion, the larger lesion, the diameter of hemorrhage vessels 0.5~<1.0 times of the diameter of the incision knife were independent risk factors for intraoperative hemorrhage during ESD. The two modeling results of the lesion length and the lesion area were very similar. Therefore, lesion length was recommended to describe lesions in clinical practice. Conclusion:A history of coronary atherosclerotic heart disease, the depressed lesion, the longer lesion, the larger lesion, the diameter of vessels 0.5~<1.0 times of that of the incision knife are independent risk factors for intraoperative hemorrhage during ESD.

Effect of early enteral nutrition on serum endotoxin and intestinal permeability in patients with severe acute pancreatitis / 中国基层医药

Objective To study the effect of early enteral nutrition ( EN ) on the serum endotoxin and intestinal permeability in patients with severe acute pancreatitis ( SAP ) .Methods Seventy patients with SAP were selected as study objects ,and they were divided into parenteral nutrition ( PN) group and EN group according to the random number table method ,with 35 cases in each group.The PN group was given PN intervention ,while the EN group was given EN intervention .The levels of serum endotoxin and the ratio of the excretion rates of urinary lactulose and mannitol excretion before and after 1 week and 2 weeks of intervention , and the levels of inflammatory factors before and after treatment were measured .Results Before intervention ,the levels of serum endotoxin and the ratio of the excretion rates of urinary lactulose and mannitol excretion had no statistically significant differences between the two groups (t=0.274,P=0.452;t=0.035,P=0.885).After 1 week and 2 weeks of intervention,the levels of serum endotoxin and the ratio of the excretion rates of urinary lactulose and mannitol excretion in the EN group were significantly lower than those in the PN group (t=9.024,10.761,P=0.000,0.000;t=6.935,8.358,P=0.000, 0.000).After treatment,the levels of TNF -α,IL-1β,IL-6 and IL-8 in the EN group were significantly lower than those in the PN group (t=12.674,10.318,9.754,8.307,P=0.000,0.000,0.000,0.002).Conclusion EN has significant influence on the serum endotoxin and intestinal permeability in patients with SAP ,and compared with PN,EN can promote the clearance of serum endotoxin ,reduce the permeability of intestinal mucosa ,and it is worth promoting.